The process of semantic analysis of natural language sentences can be regarded as the process of successively receiving new words and integrating and refining interpretations of words and part of sentences. This research has proposed new techniques for constructing natural language understanding systems based on stepwise refinement of interpretations. Our method uses variables with information which are very powerful objects in our logic programming language PAL. Objects represented by variables with information can effectively deal with varying interpretations of words and sentences. We also proposed methods of knowledge compiling for semantic analysis of sentences, method of representation of meanings of words and sentences and a new framework for finding interpretation of sentences using variables with information in PAL.具体的には,以下の諸点を研究した.(1)名詞句+の+名詞句,名詞句+は+名詞句+だ,などの意味処理の分析を進めた.(2)上記の処理を高速めるための知識コンパイル方式を提案した.(3)述部の解析を高速化するための,接続知識のコンパイル方式を整備した.(4)論理的な黒板を利用した照応理解の枠組みの基礎的な部分を構築した.(5)制約直き変数が制約の一貫管理に貢献することを示した.(6)制約付変数に基づく統一的意味表現体系を提案した.(7)制約付変数を用いた新しい意味解釈過程の枠組みを提案した.以上の研究により,段階的詳細化の観点からみた自然言語処理の基礎が構築された.